Many electronic devices require users to perform specific gestures to interact with the device, for example swiping across the screen of a smart phone to unlock the device. These devices typically require the user to physically touch the device for the gesture to be recognised. This is not always desirable. For virtual reality devices, for example, having to interact with the device by physically touching a touchscreen may limit the virtual reality experience and/or be impractical (for example if a touchscreen is positioned close to a user's eyes).
Moreover, devices typically do not provide any kind of sensory feedback to indicate that a gesture has been performed. This can also limit a virtual reality experience, as well as limiting interactivity with more conventional smart phone and other screen-based applications.